oj.uz

Submission #840203

# Submission time Handle Problem Language Result Execution time Memory
840203 2023-08-31T08:12:21 Z happypotato Longest Trip (IOI23_longesttrip) C++17
60 / 100
 377 ms 728 KB 
#include "longesttrip.h"
 
#include <bits/stdc++.h>
#pragma GCC optimize("O2")
using namespace std;
// #define int long long // remove when necessary
#define pii pair<int, int>
#define ff first
#define ss second
#define pb push_back
#define ll long long
const int mxN = 256;
vector<int> adj[mxN];
vector<int> grp[mxN];
int conn[mxN][mxN];
bool con(int x, int y) {
    if (conn[x][y] != -1) return conn[x][y];
    return (conn[x][y] = conn[y][x] = are_connected({x}, {y}));
}
int n;
int dsupp[mxN];
vector<int> nxt[mxN];
bool vis[mxN];
void resetvis() {
  for (int i = 0; i < n; i++) vis[i] = false;
}
void reset() {
  for (int i = 0; i < n; i++) {
    adj[i].clear();
    grp[i].clear();
    for (int j = 0; j < n; j++) {
      conn[i][j] = -1;
    }
    dsupp[i] = i;
    nxt[i].clear();
    vis[i] = false;
  }
}
int DSUFind(int u) {
  if (dsupp[u] == u) return u;
  return (dsupp[u] = DSUFind(dsupp[u]));
}
void DSUMerge(int u, int v) {
  u = DSUFind(u); v = DSUFind(v);
  if (u != v) dsupp[v] = u;
}
vector<int> GetPath(int st) {
  resetvis();
  vector<int> res;
  while (true) {
    res.pb(st);
    vis[st] = true;
    bool found = false;
    for (int &v : nxt[st]) {
      if (!vis[v]) {
        st = v;
        found = true;
        break;
      }
    }
    if (!found) break;
  }
  return res;
}
vector<int> MakePath(vector<int> &v) {
  if (v.size() == 1) return {v[0]};
  if (v.size() == 2) {
    if (con(v[0], v[1])) return {v[0], v[1]};
    else return {v[0]};
  }
  if (v.size() == 3) {
    if (con(v[0], v[1]) && con(v[0], v[2])) return {v[1], v[0], v[2]};
    if (con(v[0], v[1]) && con(v[1], v[2])) return {v[0], v[1], v[2]};
    if (con(v[0], v[2]) && con(v[1], v[2])) return {v[0], v[2], v[1]};
    if (con(v[0], v[1])) return {v[0], v[1]};
    if (con(v[0], v[2])) return {v[0], v[2]};
    if (con(v[1], v[2])) return {v[1], v[2]};
    return {v[0]};
  }
  for (int i = 0; i < n; i++) {
    nxt[i].clear();
  }
  pair<pii, pii> cur = {{v[0], v[0]}, {v[1], v[1]}};
  for (int i = 2; i < (int)(v.size()); i++) {
    if (con(cur.ff.ff, cur.ss.ff)) {
      nxt[cur.ff.ff].pb(cur.ss.ff);
      nxt[cur.ss.ff].pb(cur.ff.ff);
      cur.ff.ff = cur.ss.ss;
      cur.ss = {v[i], v[i]};
    } else if (con(cur.ff.ff, v[i])) {
      nxt[cur.ff.ff].pb(v[i]);
      nxt[v[i]].pb(cur.ff.ff);
      cur.ff.ff = v[i];
    } else {
      conn[cur.ss.ff][v[i]] = conn[v[i]][cur.ss.ff] = 1;
      nxt[cur.ss.ff].pb(v[i]);
      nxt[v[i]].pb(cur.ss.ff);
      cur.ss.ff = v[i];
    }
  }
  int st;
  if (con(cur.ff.ff, cur.ss.ff)) {
    nxt[cur.ff.ff].pb(cur.ss.ff);
    nxt[cur.ss.ff].pb(cur.ff.ff);
    st = cur.ff.ss;
  } else if (con(cur.ff.ff, cur.ss.ss)) {
    nxt[cur.ff.ff].pb(cur.ss.ss);
    nxt[cur.ss.ss].pb(cur.ff.ff);
    st = cur.ff.ss;
  } else if (con(cur.ff.ss, cur.ss.ff)) {
    nxt[cur.ff.ss].pb(cur.ss.ff);
    nxt[cur.ss.ff].pb(cur.ff.ss);
    st = cur.ff.ff;
  } else if (con(cur.ff.ss, cur.ss.ss)) {
    nxt[cur.ff.ss].pb(cur.ss.ss);
    nxt[cur.ss.ss].pb(cur.ff.ss);
    st = cur.ff.ff;
  } else {
    vector<int> res[2];
    res[0] = GetPath(cur.ff.ff);
    res[1] = GetPath(cur.ss.ff);
 
    // cerr << "res0: ";
    // for (int &x : res[0]) cerr << x << ' ';
    // cerr << endl;
    // cerr << "res1: ";
    // for (int &x : res[1]) cerr << x << ' ';
    // cerr << endl;
 
    bool found = false;
    for (int i = 0; i < (int)(res[0].size()); i++) {
      for (int j = 0; j < (int)(res[1].size()); j++) {
        if (con(res[0][i], res[1][j])) {
          // cerr << "FOUND " << res[0][i] << ' ' << res[1][j] << endl;
          nxt[res[0][i]].pb(res[1][j]);
          nxt[res[1][j]].pb(res[0][i]);
 
          if (res[0].size() >= 3) {
            nxt[cur.ff.ff].pb(cur.ff.ss);
            nxt[cur.ff.ss].pb(cur.ff.ff);
            // cerr << "RES0 ";
            // for (int &x : res[0]) cerr << x << ' ';
            // cerr << endl;
            st = (i == 0 ? res[0].back() : res[0][i - 1]);
            // cerr << "ST " << st << endl;
            vector<int>::iterator it;
            for (it = nxt[st].begin(); it != nxt[st].end(); ++it) {
              if (*it == res[0][i]) {
                nxt[st].erase(it);
                break;
              }
            }
            for (it = nxt[res[0][i]].begin(); it != nxt[res[0][i]].end(); ++it) {
              if (*it == st) {
                nxt[res[0][i]].erase(it);
                break;
              }
            }
          } else {
            st = (res[0].size() == 2 ? res[0][i ^ 1] : res[0][i]);
          }
 
          if (res[1].size() >= 3) {
            nxt[cur.ss.ff].pb(cur.ss.ss);
            nxt[cur.ss.ss].pb(cur.ss.ff);
            int tar = (j == 0 ? res[1].back() : res[1][j + 1]);
            vector<int>::iterator it;
            for (it = nxt[tar].begin(); it != nxt[tar].end(); ++it) {
              if (*it == res[1][j]) {
                nxt[tar].erase(it);
                break;
              }
            }
            for (it = nxt[res[1][j]].begin(); it != nxt[res[1][j]].end(); ++it) {
              if (*it == tar) {
                nxt[res[1][j]].erase(it);
                break;
              }
            }
          }
 
          found = true;
          break;
        }
      }
      if (found) break;
    }
    if (!found) {
      while (true) continue;
    }
  }
 
  // cerr << "find path for: ";
  // for (int &x : v) cerr << x << ' ';
  // cerr << endl;
  
  vector<int> res = GetPath(st);
 
  // cerr << "st: " << st << endl;
  // cerr << "result: ";
  // for (int &x : res) cerr << x << ' ';
  // cerr << endl;
 
  return res;
}
vector<int> longest_trip(int N, int D)
{
  n = N;
  reset();
  
  queue<int> q;
  for (int i = 0; i < n; i++) {
     grp[i] = {i};
     q.push(i);
  }
  while (q.size() >= 3) {
     int a = q.front(); q.pop();
     int b = q.front(); q.pop();
     int c = q.front(); q.pop();
     if (are_connected(grp[a], grp[b])) {
         DSUMerge(a, b);
         for (int &x : grp[b]) grp[a].pb(x);
         grp[b].clear();
         q.push(a);
         q.push(c);
     } else if (are_connected(grp[a], grp[c])) {
         DSUMerge(a, c);
         for (int &x : grp[c]) grp[a].pb(x);
         grp[c].clear();
         q.push(a);
         q.push(b);
     } else {
         DSUMerge(b, c);
         for (int &x : grp[c]) grp[b].pb(x);
         grp[c].clear();
         q.push(a);
         q.push(b);
     }
  }
  int fina = q.front(); q.pop();
  int finb = q.front(); q.pop();
  if (are_connected(grp[fina], grp[finb])) {
      DSUMerge(fina, finb);
      for (int &x : grp[finb]) grp[fina].pb(x);
      grp[finb].clear();
  }
  
  vector<int> best = {};
  for (int i = 0; i < n; i++) {
    if (grp[i].empty()) continue;
    vector<int> res = MakePath(grp[i]);
    if (res.size() > best.size()) {
      best = res;
    }
  }
  return best;
}

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 208 KB Output is correct
2 Correct 4 ms 592 KB Output is correct

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 208 KB Output is correct
2 Correct 12 ms 208 KB Output is correct
3 Correct 14 ms 336 KB Output is correct
4 Correct 16 ms 464 KB Output is correct
5 Correct 19 ms 604 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 208 KB Output is correct
2 Correct 11 ms 208 KB Output is correct
3 Correct 17 ms 336 KB Output is correct
4 Correct 13 ms 464 KB Output is correct
5 Correct 12 ms 592 KB Output is correct
6 Correct 14 ms 208 KB Output is correct
7 Correct 14 ms 208 KB Output is correct
8 Correct 15 ms 336 KB Output is correct
9 Correct 15 ms 464 KB Output is correct
10 Correct 14 ms 584 KB Output is correct
11 Correct 14 ms 592 KB Output is correct
12 Correct 15 ms 592 KB Output is correct
13 Correct 14 ms 592 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 208 KB Output is correct
2 Correct 14 ms 208 KB Output is correct
3 Correct 11 ms 336 KB Output is correct
4 Correct 13 ms 464 KB Output is correct
5 Correct 19 ms 584 KB Output is correct
6 Correct 14 ms 208 KB Output is correct
7 Correct 8 ms 208 KB Output is correct
8 Correct 15 ms 464 KB Output is correct
9 Correct 14 ms 336 KB Output is correct
10 Correct 14 ms 592 KB Output is correct
11 Correct 15 ms 592 KB Output is correct
12 Correct 20 ms 592 KB Output is correct
13 Correct 10 ms 596 KB Output is correct
14 Correct 12 ms 208 KB Output is correct
15 Correct 14 ms 208 KB Output is correct
16 Correct 16 ms 336 KB Output is correct
17 Correct 17 ms 336 KB Output is correct
18 Correct 20 ms 336 KB Output is correct
19 Correct 13 ms 436 KB Output is correct
20 Correct 17 ms 336 KB Output is correct
21 Correct 18 ms 592 KB Output is correct
22 Correct 17 ms 588 KB Output is correct
23 Correct 15 ms 584 KB Output is correct
24 Correct 18 ms 592 KB Output is correct
25 Correct 11 ms 208 KB Output is correct
26 Correct 12 ms 208 KB Output is correct
27 Correct 9 ms 208 KB Output is correct
28 Correct 13 ms 336 KB Output is correct
29 Correct 17 ms 208 KB Output is correct
30 Correct 21 ms 336 KB Output is correct
31 Correct 23 ms 392 KB Output is correct
32 Correct 16 ms 336 KB Output is correct
33 Correct 18 ms 432 KB Output is correct
34 Correct 17 ms 336 KB Output is correct
35 Correct 18 ms 336 KB Output is correct
36 Correct 22 ms 608 KB Output is correct
37 Correct 14 ms 608 KB Output is correct
38 Correct 18 ms 608 KB Output is correct
39 Correct 23 ms 604 KB Output is correct
40 Correct 26 ms 620 KB Output is correct
41 Correct 22 ms 588 KB Output is correct
42 Correct 26 ms 592 KB Output is correct
43 Correct 21 ms 604 KB Output is correct
44 Correct 19 ms 592 KB Output is correct
45 Correct 9 ms 208 KB Output is correct
46 Correct 11 ms 208 KB Output is correct
47 Correct 18 ms 208 KB Output is correct
48 Correct 13 ms 336 KB Output is correct
49 Correct 17 ms 336 KB Output is correct
50 Correct 18 ms 392 KB Output is correct
51 Correct 46 ms 336 KB Output is correct
52 Correct 83 ms 376 KB Output is correct
53 Correct 19 ms 336 KB Output is correct
54 Correct 23 ms 432 KB Output is correct
55 Correct 29 ms 436 KB Output is correct
56 Correct 17 ms 592 KB Output is correct
57 Correct 35 ms 608 KB Output is correct
58 Correct 52 ms 600 KB Output is correct
59 Correct 154 ms 600 KB Output is correct
60 Correct 161 ms 604 KB Output is correct
61 Correct 105 ms 596 KB Output is correct
62 Correct 109 ms 608 KB Output is correct
63 Correct 126 ms 604 KB Output is correct
64 Correct 128 ms 612 KB Output is correct

Subtask #4
19.999999998 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 17 ms 208 KB Output is correct
3 Correct 14 ms 336 KB Output is correct
4 Correct 10 ms 464 KB Output is correct
5 Partially correct 13 ms 588 KB Output is partially correct
6 Correct 18 ms 208 KB Output is correct
7 Correct 15 ms 208 KB Output is correct
8 Correct 13 ms 336 KB Output is correct
9 Correct 18 ms 336 KB Output is correct
10 Partially correct 14 ms 588 KB Output is partially correct
11 Partially correct 16 ms 572 KB Output is partially correct
12 Partially correct 14 ms 608 KB Output is partially correct
13 Partially correct 18 ms 592 KB Output is partially correct
14 Correct 13 ms 208 KB Output is correct
15 Correct 13 ms 208 KB Output is correct
16 Correct 11 ms 336 KB Output is correct
17 Correct 20 ms 356 KB Output is correct
18 Correct 14 ms 380 KB Output is correct
19 Correct 16 ms 428 KB Output is correct
20 Correct 17 ms 336 KB Output is correct
21 Correct 14 ms 208 KB Output is correct
22 Correct 14 ms 208 KB Output is correct
23 Correct 18 ms 208 KB Output is correct
24 Correct 14 ms 208 KB Output is correct
25 Correct 9 ms 208 KB Output is correct
26 Correct 17 ms 336 KB Output is correct
27 Correct 17 ms 396 KB Output is correct
28 Correct 23 ms 372 KB Output is correct
29 Correct 18 ms 336 KB Output is correct
30 Correct 20 ms 440 KB Output is correct
31 Correct 19 ms 336 KB Output is correct
32 Correct 28 ms 208 KB Output is correct
33 Correct 13 ms 208 KB Output is correct
34 Correct 20 ms 208 KB Output is correct
35 Correct 20 ms 208 KB Output is correct
36 Correct 16 ms 208 KB Output is correct
37 Correct 12 ms 392 KB Output is correct
38 Partially correct 50 ms 376 KB Output is partially correct
39 Partially correct 95 ms 376 KB Output is partially correct
40 Correct 18 ms 336 KB Output is correct
41 Partially correct 21 ms 440 KB Output is partially correct
42 Partially correct 35 ms 440 KB Output is partially correct
43 Partially correct 20 ms 600 KB Output is partially correct
44 Partially correct 20 ms 592 KB Output is partially correct
45 Partially correct 20 ms 600 KB Output is partially correct
46 Partially correct 24 ms 584 KB Output is partially correct
47 Partially correct 18 ms 592 KB Output is partially correct
48 Partially correct 20 ms 596 KB Output is partially correct
49 Partially correct 19 ms 600 KB Output is partially correct
50 Partially correct 25 ms 724 KB Output is partially correct
51 Partially correct 25 ms 604 KB Output is partially correct
52 Partially correct 27 ms 600 KB Output is partially correct
53 Partially correct 25 ms 608 KB Output is partially correct
54 Partially correct 24 ms 604 KB Output is partially correct
55 Partially correct 22 ms 600 KB Output is partially correct
56 Partially correct 22 ms 604 KB Output is partially correct
57 Partially correct 21 ms 608 KB Output is partially correct
58 Partially correct 27 ms 604 KB Output is partially correct
59 Partially correct 20 ms 600 KB Output is partially correct
60 Partially correct 23 ms 596 KB Output is partially correct
61 Partially correct 30 ms 600 KB Output is partially correct
62 Partially correct 19 ms 592 KB Output is partially correct
63 Partially correct 51 ms 600 KB Output is partially correct
64 Partially correct 65 ms 612 KB Output is partially correct
65 Partially correct 132 ms 600 KB Output is partially correct
66 Partially correct 156 ms 600 KB Output is partially correct
67 Partially correct 105 ms 600 KB Output is partially correct
68 Partially correct 106 ms 600 KB Output is partially correct
69 Partially correct 170 ms 596 KB Output is partially correct
70 Partially correct 161 ms 612 KB Output is partially correct
71 Partially correct 60 ms 616 KB Output is partially correct
72 Partially correct 119 ms 600 KB Output is partially correct
73 Partially correct 218 ms 600 KB Output is partially correct
74 Partially correct 312 ms 596 KB Output is partially correct
75 Partially correct 377 ms 608 KB Output is partially correct
76 Partially correct 299 ms 604 KB Output is partially correct
77 Partially correct 56 ms 640 KB Output is partially correct
78 Partially correct 58 ms 728 KB Output is partially correct
79 Partially correct 190 ms 592 KB Output is partially correct
80 Partially correct 100 ms 644 KB Output is partially correct
81 Partially correct 225 ms 604 KB Output is partially correct
82 Partially correct 281 ms 596 KB Output is partially correct